Washington Revised Code Title 49. Labor Regulations § 49.24.080. Requirements for underground labor

(1) A safety miner shall be selected by the crew on each shift who shall check the conditions necessary to make the working place safe; such as loose rock, faulty timbers, poor rails, lights, ladders, scaffolds, fan pipes and firing lines.

(2) Ventilating fans shall be installed from twenty-five to one hundred feet outside the portal.

(3) No employee shall be allowed to “bar down” without the assistance of another employee.

(4) No employee shall be permitted to return to the heading until at least thirty minutes after blasting.

(5) Whenever persons are employed in wet places, the employer shall furnish such persons with rubbers, boots, coats and hats. All boots if worn previously by an employee shall be sterilized before being furnished to another: PROVIDED, That RCW 49.24.080 through 49.24.380 shall not apply to the operation of a railroad except that new construction of tunnels, caissons or subways in connection therewith shall be subject to the provisions of RCW 49.24.080 through 49.24.380: PROVIDED, FURTHER, That in the event of repair work being done in a railroad tunnel, no person shall be compelled to perform labor until the air has been cleared of smoke, gas and fumes.